FTM ... got my milk but baby not getting any!

Michelle Marie 👗💖❤️‍🩹 • "...I will trust and not be afraid; For God is our refuge and strength...” - Psa 46:1

My baby is 4 days old and I receive my milk yesterday. My breasts got hard and firm and I was able to nurse a couple times. Now I breastfeed baby and no milk is coming. Not sure what to do!